Piston pump



FIG. 1 is a top left side perspective view of an ornamental design for a piston pump showing our new design.

FIG. 2 is a bottom left side perspective view of the piston pump of FIG. 1.

FIG. 3 is a top right side perspective view of the piston pump of FIG. 1.

FIG. 4 is a bottom right side perspective view of the piston pump of FIG. 1.

FIG. 5 is a front view of the piston pump of FIG. 1.

FIG. 6 is a rear view of the piston pump of FIG. 1.

FIG. 7 is a left side view of the piston pump of FIG. 1.

FIG. 8 is a right side view of the piston pump of FIG. 1.

FIG. 9 is a top view of the piston pump of FIG. 1; and,

FIG. 10 is a bottom view of the piston pump of FIG. 1.

This article is a tandem piston pump that can be used in, for example, construction machinery. Four ports, a discharge port and a suction port of one piston and a discharge port and a suction port of the other piston, are arranged vertically in a row in a center in a left and right direction on a rear side of the piston pump. The broken lines illustrating a body of the piston pump form no part of the claimed design. 

CLAIM The ornamental design for a piston pump, as shown and described. 